I realize that if this were the age of witch burning or other burning of non-orthodox views, people would be getting their marshmallows ready. And please do believe me that , for reasons that escape me, every person keeping fish should be fully conversant with the nitrogen cycle, even though as it is usually taught to budding aquarists, the part relevant to them is sufficient, not entire.. However, I am now wondering why such things are so important; after being given the name of a product by Biker123, I believe, I did a 6 month test of Boyd's ChemiPure, a scavenger of nitrogenous waste as well as a test against Seachem's Purigen, which now claims to scavenge nitrate as well.. Three tanks were involved, all 30g L, to to each were introduced 12 common platies, the 3rd tank having a sufficient bio-bed. To be brief, the tanks without a bio-bed did never test positive for any of the three nitrogenous wastes that we watch for for, while the bio-bed tank did show an expectable and reasonable amount of nitrate, removed by W/Cs. I should mention that all three tanks were vastly over filtered, and the ones' having only chemical filtration where well overstocked with media (ratio 3:1 over manufactures suggestion). Again, to be brief in this question, if one effectively removes all ammonia and nitrite (both mentioned products do say that they do this principally), where would nitrate come from? I am sure of the results that I got, but not so certain if there is something that I am overlooking, and would really like some help on this. As I see it now, if a beginner freaks out due to fish loss owing to an incomplete or absent cycling, perhaps we owe it to them to suggest alternatives. BTW, this is so obvious a method that I know that I have made an error; I just need it pointed out to me, thanks, rick Also, please to remember that I truly believe that anyone keeping fish does need to know that nitrogen cycle .